Exam 3 (chapter 12 part 4) Flashcards
high intensity exercises uses ____________ fibers, causes a buildup of ____________, strong contractions cause compression of ______________ _______________, causes neuromuscular ___________, altered __________ activity, and recovery happens within ___________ to hours
glycolytic, lactate, blood vessels, fatigue, enzyme, minutes
neuromuscular fatigue is due to the depletion of _________________
acetylcholine
- lacks striations
- found in internal organs and blood vessels
- under involuntary control by the ANS
- spindle shaped
- small in size
- contains actin and myosin
- does not have sarcomeres
- dense bodies
smooth muscle
Align actin/myosin filaments in smooth muscles
dense bodies
does smooth muscle have sarcomeres?
no, no striations
does smooth muscle have actin AND myosin?
yes
do lungs have much smooth muscle? if not, what in the respiratory system does?
no, Bronchi
actin and myosin are ______________ in smooth muscle than in skeletal muscle
- myosin heads whole length giving a longer range of contraction
longer
in smooth muscle, myosin heads are along the whole length, what does this give you?
longer range of contraction
what are the 6 steps of smooth muscle excitation contraction coupling?
- Ca++ comes in from ECF through voltage gated channels,
- Ca++ triggers release of Ca++ from SR,
- Ca++ binds to calmodulin,
- Ca++calmodulin activates MLCK,
- MLCK phosphorylates myosin,
- cross bridge cycling
kinase that phosphorylates the myosin head in smooth muscule
MLCK
to relax smooth muscle:
- phosphatase removes phosphate from ____________
- _____________ is removed from cytoplasm
Myosin,
Ca2+
what are the 2 ways that Ca++ is removed from the cytoplasm in smooth muscle?
Ca++ ATPase, Ca++/Na+ countertransport
smooth muscle is innervated by the _______________ nervous system
autonomic (sympathetic and/or parasympathetic)
is smooth muscle excitatory or inhibitory?
both
